My Honda Rebel managed to beat one of the pistons into a billion pieces and bend the offending piston rod. I've identified all the damaged parts and ordered replacements, or had them repaired ( cylinder wall honed and pressure tested ) so now I just need to remove all the metal filings that have filled the crank case.

The piston was aluminum, so I can't use a magnet to pull out the metal filings. I was thinking about filling some of the smaller spaces with polyurethane foam to grab the filings, before pulling the foam out, and hopefully most of the aluminum filings with it.

Will this approach work, or are there better, standard ways of removing metal shavings from a crank case?